Lactobacillus casei Zhang的甲基转移酶突变体与其野生型的代谢组学比较

Metabolomic Comparison of Lactobacillus casei Zhang Methyltransferase Mutant and Wild Type

摘要:

DNA甲基化作为表观遗传学的重要组成部分，在细菌的很多生理过程中发挥着重要作用。作者基于超高效液相色谱-质谱联用非靶向代谢组学技术，比较DNA甲基转移酶突变体Lactobacillus casei （L. casei）Zhang ΔpglX与野生型L. casei Zhang在对数生长前期（4 h）的代谢差异。共鉴定得到23个显著差异代谢物（P<0.05），主要富集在氨酰-tRNA生物合成、不饱和脂肪酸生物合成、D-谷氨酰胺和D-谷氨酸代谢及半乳糖代谢等代谢途径。结果表明，DNA甲基化表型在对数生长前期可能会影响菌株对氨基酸的合成和利用；另一方面，DNA甲基化表型在对数生长前期可能会调节菌株细胞膜脂肪酸成分，改变细胞膜的通透性和流动性。

Abstract:

As a crucial part of epigenetics, DNA methylation plays an indispensable role in various physiological processes in bacteria. Here, we compared the metabonomics of DNA methylation of mutant strain Lactobacillus casei (L. casei) Zhang ΔpglX and wild strain L. casei Zhang in the early logarithmic growth phase(4 h) using ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) non-targeted metabolomics technology. A total of twenty-three significantly different metabolites were identified(P <0.05), primarily enriched in pathways such as aminoacyl-tRNA biosynthesis, un-saturate fatty acids biosynthesis, D-glutamine and D-glutamate metabolism, and galactose metabolism. The results suggest that DNA methylation phenotype may affect the synthesis and utilization of amino acids in bacterial strains during early logarithmic growth. On the other hand, DNA methylation phenotypes may modulate the composition of cellular membrane fatty acids, altering membrane permeability and fluidity.